1. Field of the Invention
The present invention relates to a radar device for an automotive radar system, and more particularly, to a radar device capable of reducing required routing and simplifying an assembly procedure.
2. Description of the Prior Art
A blind spot detection system is a vehicle safety technology achieving advance warning by utilizing millimeter wave radar sensing technology, which detects obstacle conditions in blind spots of the vehicle by an image self-identification method of machine vision. If the system detects existence of a specific obstacle in the blind spot, a warning light or sound signal is proactively provided for the driver to determine a driving direction, so as to avoid traffic accidents due to negligence or blind spot of the driver. The conceptual operation diagram is shown in FIG. 1.
As shown in the FIG. 1, the dotted region on the rear left and right corners of a vehicle 100 is considered as the blind spots (i.e., the blind region). The conventional blind spot detection system disposes two wireless signal transceivers 100 inside the bumper for detecting the obstacles by transmitting and receiving of millimeter wave wireless signals. Note that, FIG. 1 is used to illustrate the operation concept of a blind spot detection system, so the relative positions of the wireless signal transceivers 12, 14 are labeled. Generally, the wireless signal transceivers 100, 102 are disposed inside the bumper so that they are hidden from perception. Moreover, FIG. 1 shows that the wireless signal transceivers 100, 102 are disposed on both corners of the rear bumper according to the positions of the blind regions 12, 14. In such a condition, the positions of the wireless signal transceivers 100, 102 need to be clarified and adjusted during installation, which causes an increase of the installation complexity.
In addition, each of the wireless signal transceivers 100, 102 includes three major portions: a digital signal processing (DSP), an electrical control unit (ECU), and a radio-frequency (RF) circuit. Since these circuits or units require complying with automotive specifications (e.g. temperature, vibration, etc.), the manufacturing cost cannot be effectively reduced, which even creates a barrier for popularizing the wireless signal transceivers to majority of the vehicles. Considering that the blind spot detection system helps to effectively reduce traffic accidents, the manufacturing cost of the blind spot detection system needs to be further reduced in order to increase the adoption rate, and therefore decrease social costs of traffic accidents.
Furthermore, the detection signals obtained from the wireless signal transceivers 100, 102 need to be transmitted to the electrical control unit inside the vehicle for timely generating the warning light or sound for the driver. In such a situation, since the wireless signal transceivers 100, 102 are disposed on both corners of the rear of the vehicle, the complexity of the signal routing is increased and a lot of assembling procedures are required. Therefore, reliability or satisfaction to the vehicle may become an issue.
On the other hand, since shock-absorbing Styrofoam or glass fiber is usually disposed inside the vehicle bumper, the available space is limited. Therefore, the blind spot detection system vendor needs to be involved into the decision loop of materials and thickness of the bumper during the vehicle design and iteratively modifies the wireless transceiver design in order to meet the requirement of the vehicle vendor. As a result, the timeliness is hard to achieve. In addition, if the automotive radar system is produced for sales of after-market, i.e. vendors for the radar systems are not able to participate in decision-making of materials and thickness of the bumper. In such a condition, it becomes much more difficult to design a blind spot detection system that complies with majority of the vehicles.
Thus, it is a common goal in the industry to effectively reduce the installation complexity and manufacturing cost of the blind spot detection system, and make the blind spot detection system applicable to the after-market.